The Congress is preparing itself to part with the ministries of coal, environment and forests, and power whenever the Samajwadi Party signals that it is ready to join the 12-party United Progressive Alliance.

The ministries of coal and environment and forests are currently in the temporary charge of the prime minister and all the indications are that the current power minister, Sushil Kumar Shinde, might be moved to Maharashtra as chief minister, creating a vacancy, top sources in the government said.

"But that does not mean we change what we stand for," Amar Singh said.

However, the SP bought more time on Thursday and postponed a decision on supporting the government on the controversial Indo-US civil nuclear deal.

The SP's support becomes critical because the four Left parties -- the Communist Party of India (Marxist), Communist Party of India, Forward Bloc and Revolutionary Socialist Party (RSP) -- that vote with the UPA in Parliament have threatened to withdraw support if the nuclear deal is pushed through. The withdrawal would have sent the UPA into minority.

Thursday's decision by the SP, which has 39 seats in Parliament, came after the so-called 50-member Third Front United National People's Alliance comprising parties opposed to the Congress and the BJP, resolved to stand united.

The SP is the biggest constituent of the 50-member UNPA. Others include Asom Gana Parishad (2 MPs) Telugu Desam Party (5 MPs), National Conference (2), independents like Babu Lal Marandi and the Indian National Lok Dal (no MPs).

"We will not oppose anything in national interest and certainly we feel that communalism is a bigger threat than the nuclear deal," said Amar Singh.

The UNPA also said at a joint press conference that it will take the opinion of non-partisan scientists on the nuclear deal.

"The Congress referred to the matter as an issue over which only the Cabinet need decide, there is confusion on the matter. The National Security Advisor yesterday tried to remove some confusion, but we will also take independent opinion," said Amar Singh.

PTI reports former President and scientist APJ Abdul Kalam [Images] on Thursday told Yadav and Amar Singh that the Indo-US nuclear deal was beneficial for the country.

The UNPA thinks Kalam is the 'best scientist in India'.

INLD chief Om Prakash Chautala said the UNPA would not take a decision before Prime Minister Manmohan Singh's departure for Japan [Images] for the G-8 summit on July 7.

Yadav reiterated that they would not let 'communal forces' take over, or act against national interest, the strongest signal that the SP appeared ready to come to an agreement with the Congress.

Most Congressmen saw the UNPA's stance as a way to bargain with the Congress as the price for their support. The most nuanced was the stance of the TDP, which supports the nuclear deal but has an electoral alliance with the CPI M, the largest of the Left parties and most bitter critic of the agreement.

Meanwhile, Mulayam Singh Yadav told media persons that the SP would do nothing that was not in national interest but added that it was important to keep communal elements out of power.